Cam Variator failure

I did not realize there was a self tensionner, so is there no initial tension setting, you just put the belt on and tension is set? How many of these things have actually failed?
Maybe some do have defects from production or are the Variators themselves being over torqued when installed in the cam and therefore under excessive stress at the threaded portion?
I am not a designer but if I had to design a replacement it would have to be a new cam to accept a new larger/stronger Variator if that is the problem.
Like I said it could just be incorrectly installed that’s why only a few have failed. One thing is true, they are failing and there is a problem.
I am not trying to slag off Ferrari or the 360, I love them and as a 360 buyer myself I am starting my research.
I am very interested in any potential problems and how they can be overcome/prevented as I want my Ferrari to last a very long time with minimum expense. If you know of a problem, preventative maintenance can be performed, in this case install a new Variator myself and replacement at a major if it turns out that the Variator is at fault.
Has anyone got any pictures or dimensions of pre and post mod Variators, I would like to see the difference between the two.
And I definitely don't want an Aircraft to fall out of the sky either, I could not live with myself if it was my fault!

 

Goodmorning Guys! The only problem I see with just replacing the variators during the major is that they are also failing in some cases, which leads me to believe there is a problem with defects in production that in theory could be addressed by "x-raying" (can't remember the technical term) and see if any stress cracks are present. Be great it it could be done with the variator still in place as this would also address the over torquing issue, then whatever the outcome proceed from there... just my 2cts.

 

I am not an ME, nor do I have any experience machining and modding engine parts, but the first thing that occurs to me is that this design could be improved by the addition of two locking pins - like a shear pin in a boat prop, but machined from an alloy that's not designed to shear.

The very crude sketch below is an example. Drill two holes in the end of the cam shaft and two holes in the variator. The cylindrical pins would need to be a tight fit of course, which might make removing the variator difficult.
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Oh... duh! Guess my brain was not engaged or I was in another world where it is possible to insert the pins after screwing on the variator. Oh well... next idea?

 

There is not an automatic tenisoner.
there is a tensioner that will compensate for the thermal expansion of the engine but proper tension of the belt is critical. I suspect incorrect tension over or under can creat the concern. Overteniosn obviously puts additional side load on the variator and the radius at the flange. Under tension can result in harmonics from the belt that can also be very destructive. As the concern is not generally evident until the variator is laying in the bellypan it will be hard to determine what the source of the failure is.